Add 'make_generator(value)'

SSoelvsten · Nov 17, 2023 · e327179 · e327179
1 parent 25b0c05
commit e327179
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Showing 3 changed files with 23 additions and 27 deletions.
diff --git a/src/adiar/bdd/restrict.cpp b/src/adiar/bdd/restrict.cpp
@@ -84,16 +84,9 @@ namespace adiar
   __bdd bdd_restrict(const exec_policy &ep,
                      const bdd &f, bdd::label_type var, bool val)
   {
-    bool gen_called = false;
-    auto gen = [&gen_called, &var, &val]() -> optional<pair<bdd::label_type, bool>> {
-      if (gen_called) {
-        return make_optional<pair<bdd::label_type, bool>>();
-      }
-      gen_called = true;
-      return make_pair<bdd::label_type, bool>(var, val);
-    };
-
-    return bdd_restrict(ep, f, gen);
+    return bdd_restrict(ep,
+                        f,
+                        make_generator(make_pair<bdd::label_type, bool>(var, val)));
   }
 
   __bdd bdd_restrict(const bdd &f, bdd::label_type var, bool val)

diff --git a/src/adiar/functional.h b/src/adiar/functional.h
@@ -111,6 +111,9 @@ namespace adiar
     };
   }
 
+  // TODO: Add make_generator(begin, end) for rvalue iterators; they go out of
+  //       scope at return!
+
   ////////////////////////////////////////////////////////////////////////////
   /// \brief Wrap an `adiar::internal::file_stream` into a generator function.
   ////////////////////////////////////////////////////////////////////////////
@@ -128,6 +131,21 @@ namespace adiar
     };
   }
 
+  ////////////////////////////////////////////////////////////////////////////
+  /// \brief Wrap a single value into a generator.
+  ////////////////////////////////////////////////////////////////////////////
+  template<typename RetType>
+  inline generator<RetType>
+  make_generator(const RetType &r)
+  {
+    return [=, end = false]() mutable {
+      if (end) { return make_optional<RetType>(); }
+
+      end = true;
+      return make_optional(r);
+    };
+  }
+
   /// \}
   //////////////////////////////////////////////////////////////////////////////
 

diff --git a/src/adiar/zdd/subset.cpp b/src/adiar/zdd/subset.cpp
@@ -8,19 +8,6 @@
 
 namespace adiar
 {
-  // TODO: Merge with the generator in `bdd_restrict(f, var, val)`.
-  inline auto make_generator(const zdd::label_type &var, bool &gen_called)
-  {
-    adiar_assert(!gen_called);
-    return [&gen_called, &var]() -> optional<zdd::label_type> {
-      if (gen_called) {
-        return make_optional<zdd::label_type>();
-      }
-      gen_called = true;
-      return var;
-    };
-  }
-
   template<assignment FIX_VALUE>
   class zdd_subset_labels
   {
@@ -152,8 +139,7 @@ namespace adiar
 
   __zdd zdd_offset(const exec_policy &ep, const zdd &A, zdd::label_type var)
   {
-    bool gen_called = false;
-    return zdd_offset(ep, A, make_generator(var, gen_called));
+    return zdd_offset(ep, A, make_generator(var));
   }
 
   __zdd zdd_offset(const zdd &A, zdd::label_type var)
@@ -251,8 +237,7 @@ namespace adiar
 
   __zdd zdd_onset(const exec_policy &ep, const zdd &A, zdd::label_type var)
   {
-    bool gen_called = false;
-    return zdd_onset(ep, A, make_generator(var, gen_called));
+    return zdd_onset(ep, A, make_generator(var));
   }
 
   __zdd zdd_onset(const zdd &A, zdd::label_type var)